+static int audit_set_loginuid_perm(kuid_t loginuid)
+{
+ /* if we are unset, we don't need privs */
+ if (!audit_loginuid_set(current))
+ return 0;
+ /* if AUDIT_FEATURE_LOGINUID_IMMUTABLE means never ever allow a change*/
+ if (is_audit_feature_set(AUDIT_FEATURE_LOGINUID_IMMUTABLE))
+ return -EPERM;
+ /* it is set, you need permission */
+ if (!capable(CAP_AUDIT_CONTROL))
+ return -EPERM;
+ /* reject if this is not an unset and we don't allow that */
+ if (is_audit_feature_set(AUDIT_FEATURE_ONLY_UNSET_LOGINUID) && uid_valid(loginuid))
+ return -EPERM;
+ return 0;
+}
+
+static void audit_log_set_loginuid(kuid_t koldloginuid, kuid_t kloginuid,
+ unsigned int oldsessionid, unsigned int sessionid,
+ int rc)
+{
+ struct audit_buffer *ab;
+ uid_t uid, ologinuid, nloginuid;
+
+ uid = from_kuid(&init_user_ns, task_uid(current));
+ ologinuid = from_kuid(&init_user_ns, koldloginuid);
+ nloginuid = from_kuid(&init_user_ns, kloginuid),
+
+ ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
+ if (!ab)
+ return;
+ audit_log_format(ab, "pid=%d uid=%u old auid=%u new auid=%u old "
+ "ses=%u new ses=%u res=%d", current->pid, uid, ologinuid,
+ nloginuid, oldsessionid, sessionid, !rc);
+ audit_log_end(ab);
+}
+